1. Field of the Invention
The present invention generally relates to image processing apparatuses, methods for processing an image and computer-readable recording media for causing a computer to process images, and more particularly to an image processing apparatus, a method for processing an image and a computer-readable recording medium for causing a computer to process images which are capable of processing an image automatically with a high degree of accuracy and eliminating image noises.
In the newspaper industry or the like industry, it is required to process images. In image processing, a special image processing technology, for example, an image correction technology, is needed but the operation for the image correction is not easy and generally only a specialist can carry out the operation.
Accordingly, the auto image processing technology with high accuracy is desired.
2. Description of the Related Art
Conventionally, several processes are conducted for an image. A white balance correction is processed to correct colors that are used for the entire image and cause an improperly white balanced image. A contrast expansion is processed to enlarge a brightness range. A leveling is processed to make uniform a brightness of the entire image in order to provide it with clear contrast. A xcex3-conversion is processed to adjust a brightness in a dark region in order to provide it with clear contrast.
In addition, a saturation intensity and a hue intensity are processed for an image.
In conventional image processing, specialists determine each correction degree based on their knowledge while they process an image. That is, conventionally, the specialists determine each correction degree while they display the image on a display unit or print out the image on a sheet.
Moreover, a highlight value defined as the brightest value in the image and a shadow value defined as the darkest value in the image are detected. In the conventional image processing, the brightest value in the image is mechanically detected for the highlight value and the darkest value in the image is mechanically detected for the shadow value.
However, in the conventional image processing, the specialists have to indicate the correction degree for the conspicuous color correction or the gradation correction while they display the image on the display unit. Disadvantageously, the conventional image processing is limited to the specialist. Thus, the specialists have to carry out several complicated procedures and operations.
Furthermore, in conventional image processing, since the brightest value in the image is mechanically detected for the highlight value and the darkest value in the image is mechanically detected for the shadow value, noises existing in the image affect the detection so that it is difficult to detect an accurate highlight value and an accurate shadow value.
Consequently, the conventional image processing can not achieve the highly accurate highlight value and the highly accurate shadow value.
It is a general object of the present invention to provide an image processing apparatus, a method for processing an image and a computer-readable recording medium for causing a computer to process images in which the above-mentioned problems are eliminated.
A more specific object of the present invention is to provide the image processing apparatus, the method for processing an image and the computer-readable recording medium for causing a computer to process an image which are capable of processing an image automatically with high accuracy and eliminating image noises.
The above objects of the present invention are achieved by an image processing apparatus for processing an image, including: a color space transforming part transforming an input color space of an input image to a process color space of a processing image having pixels having a luminance value; a HL/SD values detecting part detecting a HL value that shows a brightest luminance value of the pixels of the processing image and an SD value that shows a darkest luminance value of the pixels of the processing image; a white balance correcting part correcting an improper white balance of the processing image; a gradation correcting part correcting a luminance gradation of the processing image based on a gradation correction line; a leveling part leveling a luminance distribution of the processing image based on variances and leveling rates of the processing image; and a xcex3-converting part converting a luminance average of the processing image to a xcex3-value and correcting the luminance of the processing image based on the xcex3-value, thereby eliminating image noises.
According to the present invention, the image processing apparatus makes it possible to process an image automatically with a high accuracy and eliminate image noises effectively, instead of using specialists.
Also, the above objects of the present invention are achieved by a method for processing an image including the steps of: (a) transforming an input color space of an input image to a process color space of a processing image having pixels having a luminance value; (b) detecting a HL value that shows a brightest luminance value of the pixels of the processing image and an SD value that shows a darkest luminance value of the pixels of the processing image; (c) correcting an improper white balance of the processing image; (d) correcting a luminance gradation of the processing image based on a gradation correction line; (e) leveling a luminance distribution of the processing image based on variances and leveling rates of the processing image; and (f) converting a luminance average of the processing image to a xcex3-value and correcting the luminance of the processing image based on the xcex3-value, thereby eliminating image noises.
According to the present invention, it is possible to provide the method for processing an image that can process an image automatically with a high accuracy and eliminate image noises effectively, instead of using specialists.
Furthermore, the above objects of the present invention are achieved by a computer-readable recording medium recorded with program code for causing a computer to process an image, said program comprising the code for: (a) transforming an input color space of an input image to a process color space of a processing image having pixels having a luminance value; (b) detecting a HL value that shows a brightest luminance value of the pixels of the processing image and an SD value that shows a darkest luminance value of the pixels of the processing image; (c) correcting an improper white balance of the processing image; (d) correcting a luminance gradation of the processing image based on a gradation correction line; (e) leveling a luminance distribution of the processing image based on variances and leveling rates of the processing image; and (f) converting a luminance average of the processing image to a xcex3-value and correcting the luminance of the processing image based on the xcex3-value, thereby eliminating image noises.
According to the present invention, it is possible to provide the computer-readable recording medium recorded with program code for causing a computer to process an image that can process an image automatically with a high accuracy and eliminate image noises effectively, instead of using specialists.